Canola Weed Management

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CANOLA WEED MANAGEMENT Eric P. Prostko and Tim
L. Grey Extension Weed Specialist and Research
Weed Scientist The University of Georgia
April 2007
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Before Getting Started

• What herbicides were used in previous crops?
• Canola is very sensitive to herbicide residues!!

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Canola Rotation Restrictions
FB Field Bioassay
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Avoid Planting Canola in Wild Radish/Mustard
Fields
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Follow All UGA Recommended Production Practices

• Adapted Variety
• Planting Date
• North Zone (September 10 to October 25)
• South Zone (October 10 to November 15)
• Row Spacing (6-12)
• Seeding Rate (4-6 lbs/A)
• Fertility Management

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Herbicides For Use in Georgia Canola

• Glyphosate
• at-planting but before crop emergence
• Treflan,Trilin, etc.
• PPI
• Select/Arrow, Poast, Assure/Targa
• POST (grass control)
• Beyond
• POST
• Clearfield varieties only!!!!

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Trifluralin in Canola

• Incorporate to depth of 2-3 within 24 hours of
  application
• 2-pass system
• 0.50-0.75 lb ai/A
• some control of winter annual grasses, henbit,
  and chickweed
• no control of wild radish/mustard
• Better than nothing!

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• Clearfield Canola Production Systems
• Non-GMO
• Beyond (imazamox) is only herbicide registered
  for use in U.S.
• Based on UGA field trials, eliminates concerns
  for Cadre (imazapic) carryover problems.
  However, Clearfield canola is NOT listed on Cadre
  label.

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• Clearfield Canola varieties only!!!!!
• Beyond 1AS (imazamox)
• 4 oz/A NIS _at_ 0.25 v/v UAN _at_ 2.5 v/v
• weeds less than 3 tall
• In UGA field trials, Beyond has provided good to
  excellent control of Italian ryegrass, wild
  radish and shepherds-purse when applied between
  24 and 37 DAP.
• 515/gal (16.09/A)

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• ROTATIONAL CROP RESTRICTIONS FOR BEYOND
• 3 months wheat
• 4 months barley, rye
• 8.5 months field/sweet corn
• 9 months cabbage, cantaloupe, carrot, cotton,
  cucumber, grain sorghum, oats, onion, peanut,
  pepper, tobacco, tomato, turnip, watermelon
• 18 months non-Clearfield canola

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Weed Control in Clearfield Canola with Beyond 1AS
(4 oz/A) COC (1 v/v) 37 UAN (2 qts/A)
Grey et al. 2006. Weed Technology 20551-557
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Stinger

• clopyralid
• labeled but not yet recommended by UGA
• 3 lb ai/gal
• 4-8 oz/A (15-30/A)
• 2 to 6 leaf stage of canola
• 50 day PHI
• Canada thistle, sowthistle, dandelion, chamomile
• Rotations
• 0 months field corn, wheat, barley, oats
• 10.5 months grain sorghum, onions, sunflowers
• 18 months all other crops

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Other Types of Herbicide-Resistant Canola

• Roundup-Ready (RR)
• Liberty-Link (LL)
• both are not currently labeled for use in Georgia
• Why?
• Developed after Georgia stopped growing canola on
  a commercial basis
• varieties more susceptible to blackleg
• volunteer problem in other RR crops
• herbicide resistance issues

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Weed Control in RR-Canola with Roundup Weathermax
5.5SL (22 oz/A)
Grey et al. 2006. Weed Technology 20551-557
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Weed Control in LL-Canola with Liberty 1.67SL (34
oz/A) 21 AMS (3 lb/A)
Grey et al. 2006. Weed Technology 20551-557
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UGA Weed Science www.gaweed.com